The WA is a GR Pottery Forms bat system to turn a slab into a plate. The WA helps to cut an even lip and a foot ring to a thrown foot in one sitting. The standard round GR Pottery Forms now come with a drill hole to fit onto this bat system. The center hole allows the maker to push the spacer up from the bottom to lift the form and slab from the WA surface helping to eliminate finger prints. It seems really complicated, but you have to try it to experience how fun and efficient is is to make plates.